Polymerization catalyst process and catalyst

ABSTRACT

1. A CATALYST SYSTEM FORMED ON ADMIXING AN ORGANOMETAL COMPOUND OF THE FORMULA MRN WHEREIN M IS A METAL OF GROUP I-A, II-A, III-A AND IV-A OF THE PERIODIC TABLE, N IS THE VALENCE OF M AND R IS A RADICAL SELECTED FROM THE GROUP CONSISTING OF ALKYL, CYCLOALKYL AND ARYL HAVING FROM 1 TO 20 CARBON ATOMS WITH A TITANIUM TRICHLORIDE-ALUMINUM TRICHLORIDE COMPLEX OF THE FORMULA TICL3-1/3ALCL3, AN ORGANOALUMINUM DIHALIDE OF THE FORMULA RALX2 WHEREIN X IS A HALOGEN AND R IS A MEMBER OF THE GROUP CONSISTING OF ALKYL, CYCLOALKYL AND ARYL RADICALS HAVING FROM 1 TO 20 CARBON ATOMS AND A SILAZANE SELECTED FROM THE GROUP CONSISTING OF R3SI-NR&#39;&#39;-SIR3, (R3SI3-N, R3SI-NR&#39;&#39;-SIR2-NR&#39;&#39;-SIR3 AND   R&#39;&#39;(R2SINH)YR&#39;&#39;   WHEREIN R IS A MEMBER OF THE GROUP CONSISTING OF ALKYL, CYCLOALKYL AND ARYL RADICALS HAVING FROM 1 TO 20 CARBON ATOMS, R&#39;&#39; IS R OR HYDROGEN AND Y IS AN INTEGER FROM 4 TO 50, AND WHEREIN THE MOLAR RATIO OF SAID RAIX2 COMPOUND TO SAID TICL3-1/3ALCL3 COMPOUND IS IN THE RANGE OF 0.5:1 TO 10:1, THE MOLAR RATIO OF SAID SILAZANE COMPOUND TO SAID TICI3-1/3ALCL3 COMPOUND IS IN THE RANGE OF 0.25:1 TO 7.5:1 AND THE MOLAR RATIO OF SAID MRN COMPOUND TO SAID TICI3-1/3ALCL3 COMPOUND IS IN THE RANGE OF 0.5:1 TO 7.5:1 AND WHEREIN THE MOLAR RATIO OF SAID RALX2 COMPOUND TO SAID MRN COMPOUND IS IN THE RANGE OF 5:1 TO 5:2. FORMED LOW MOLECULAR WEIGHT AND HIGH MOLECULAR WEIGHT POLYMERS OF THE RESPECTIVE ELASTOMERS, IN THE RATIO OF 0.7 TO 1.3 PARTS BY WEIGHT OF THE LOW MOLECULAR WEIGHT POLYMER PER 1 PART BY WEIGHT OF THE HIGH MOLECULAR WEIGHT POLYMER, IN WHICH, FOR THE EPDM ELASTOMERIC SYSTEM, THE LOW MOLECULAR WEIGHT POLYMER IS AN EPDM HAVING A MOLECULAR WEIGHT AVERAGE LESS THAN 25,000 AND THE HIGH MOLECULAR WEIGHT POLYMER IS AN EPDM HAVING AN AVERAGE MOLECULAR WEIGHT MEASURED BY MOONEY LEVEL OF ML1+8 AT 300*F WHICH IS GREATER THAN 100 AND IN WHICH, FOR THE EPM ELASTOMERIC SYSTEM, THE LOW MOLECULAR WEIGHT POLYMER IS AN EPM HAVING AN AVERAGE MOLECULAR WEIGHT OF LESS THAN 10,000 AND THE HIGH MOLECULAR WEIGHT POLYMER IS AN EPM HAVING AN AVERAGE MOLECULAR WEIGHT MEASURED BY MOONEY LEVEL OF ML1+8 AT 300*F WHICH IS GREATER THAN 90, SEPARATING THE BLENDED SOLIDS BY COAGULATION, AND PROCESSING THE SOLID BLEND BY MILLING OR EXTRUSION.

United States Patent Office 3,554,993 POLYMERIZATION CATALYST PROCESS AND CATALYST Charles W. Moberly and Gerald R. Kahle, Bartlesville, Okla, assignors to Phillips Petroleum Company, a corporation of Delaware No Drawing. Filed Sept. 2, 1965, Ser. No. 484,717 Int. Cl. C08f 1/56 U.S. Cl. 26093.7 5 Claims This invention relates to the polymerization of olefins to form solid polymers. In one aspect it relates to improved catalysts for such a polymerization. In another aspect it relates to a process for producing solid polymers of olefins so as to obtain improved yield, improved polymer flexural modulus and/or improved xylenes-soluble content of the polymer.

Polymers of alpha-olefins, particularly of propylene, have long been known and numerous procedures have been disclosed for their production. These polymers are characterized by a greater or lesser degree of stereospecificity, i.e., the presence of a certain amount of a crystalline component frequently designated as isotactic polymer. Many of the useful properties of these polymers such as ultimate tensile, hardness, range of melting temperatures, etc. appear to depend upon the stereospecificity of the polymer. Flexural modulus, a property readily measurable by standard procedures, provide a reliable and consistent means for characterizing these polymers. The higher the stereospecificity of a polymer, the higher the flexural modulus values are found to be. For a commercially attractive product, flexural modulus values must be high, preferably above 200,000 p.s.i. and more preferably above 225,000 p.s.i. Heretofore it has frequently been necessary to extract amorphous fractions of the polymer in order to provide pro-ducts having flexural moduli in this range. It is therefore highly desirable to minimize the production of amorphous polymer, as measured for example by the amount of polymer soluble in mixed xylenes. 7

Another requirement for these polymerization procedures is a high level of productivity of polymer based on catalyst. The stereospecific catalyst systems used in these operations are expensive and cannot be regenerated. Thus, a high productivity in pounds of useful polymer per pound of catalyst is an important feature of any commercially attractive process.

An object of this invention is to provide an improved process for the production of olefin polymers.

Another object of this invention is to provide a polymerization process in which there is obtained an increase in polymer yield, an increase in flexural modulus and/ or a decrease in the xylenes-soluble content of the polymer.

A further object of this invention is to provide novel catalyst systems which when employed in a polymerization process results in the improving of the polymer yield, flexural modulus and/or xylenes-solubles of the resulting polymer.

Other aspects, objects and the several advantages of this invention will be apparent to those skilled in the art upon consideration of this disclosure.

According to our invention We have discovered that l-olefin polymers can be obtained in improved yields with increased flexural modulus and/ or decreased xylenessoluble content when the polymerization is conducted in the presence of an organometal modified catalyst system formed by admixing (A) an organoaluminum dihalide, RAlX wherein R is an alkyl, cycloalkyl, or aryl group having from 1 to 20 carbon atoms and X is a halogen selected from the group consisting of fluorine, chlorine, bromine, and iodine, (B) a ,titanium trichloride-aluminum trichloride complex resulting from the reaction of 3,554,993 Patented Jan. 12, 1971 titanium tetrachloride and aluminum and having the approximate formula TiCl /3 AlCl and (C) a compound selected from the group consisting of: (l) a substituted silane having the formula (RO)xSiR wherein R is hydrogen or R, R is an alkyl, cycloalkyl or aryl radical having from 1 to 20 carbon atoms, and x is at least 1 and not more than 4; (2) triethylenediamine; (3) an N- organo-substituted phosphoramide of the formula wherein R is an alkyl, cycloalkyl or aryl radical having from 1 to 20 carbon atoms; (4) an onium halide compound of the formula R ZX wherein Z is nitrogen, phosphorous, oxygen or sulfur, X is a halogen selected from the group consisting of fluorine, chlorine, brominefor iodine, m is 3 or 4 and R is an alkyl, cycloalkyl or aryl radical having from 1 to 20 carbon atoms; (5) an amide of the formula (a) wherein R is a radical selected from the group consisting of hydrogen, an alkyl radical containing 1 to 20 carbon atoms, phenyl, carboxyl, alkoxy, N(R wherein each R is an alkyl radical containing 1 to 4 carbon atoms, and

wherein z is an integer of l to 4, and R R R and R are radicals selected from the group consisting of H, alkyl radical containing 1 to 8 carbon atoms, phenyl and cyclohexyl,

wherein z is an integer of 1 to 4, and R is a radical selected from the group consisting of alkyl radicals containing l to 4 carbon atoms and phenyl; (6) a silazane selected from the group consisting of R Si-NRSiR (R Si) -N, R SiNR'-SiR --NR'SiR and wherein R is an alkyl, cycloalkyl, or aryl radical having from 1 to 20 carbon atoms, R is R .or hydrogen, and y is an integer from 4 to 50.

The enumeration of alkyl, cycloalkyl and aryl radicals herein in defining the formulas is intended to include the various mixed radicals such as alkaryl, aralkyl, alkylcycloalkyl, cycloalkylaryl, and the like.

The organometal compounds suitable for use in the modification of the three component system so as to obtain the improved results of the instant invention are represented by the formula MR where M is a Group I-A, II-A, III-A or IV-A metal (Periodic System of Lange, Handbook of Chemistry, 8th edition, pages 56-57), i.e., lithium,

sodium, potassium, rubidium, cesium, beryllium, magnesium, calcium, strontium, barium, aluminum, gallium, indium, thallium, tin, lead, and germanium, R is an alkyl, cycloalkyl or aryl radical having from 1 to 20 carbon atoms, and n is the valence of M.

, .Examples of the MR compounds that can be used are butyllithium, dicyclohexylmagnesium, triethylalumium, tetraphenyltin, hexylsodium, Z-naphthylpotassium, 3- cyclohexylbenzylrubidium, eicosylcesium, didodecylberyllium, di(4,5-dipentyl-l-naphthyl)calcium, di(3-methylcycloentpyl)stronitium, di(3 cyclohexylphenyl)barium, tri(3 phenanthryDgallium, tri(4 tetradecylcyclohexyl) indium, trioctylthallium, tetra(4,4-diphenylbutyl)germanium, tetraethyllead, triisobutylaluminum, and the like.

The compounds represented by the formula RAlX and and utilized as component A of the catalyst system are well known in the art. Examples are ethylaluminum dichloride, ethylalumium dibromide, ethylaluminum diiodide, npropylaluminum dichloride, n-amylaluminum dibromide, tert-butylaluminum dichloride, eicosylaluminum diiodide, cyclohexylaluminum dichloride, phenylaluminum dichloride, 3-methylphenylaluminum dibromide, paratolylaluminum difluoride, 4-phenylcyclohexylaluminum difluoride, 3- propylbenzylamluminum dichloride, benzylaluminum diiodide, and l-naphthylaluminum dichloride. Preferably, an alkylaluminum dichloride is used.

The titanium cholride-aluminum chloride complex utilized as component B of the catalyst system according to this invention is also well known in the art. It can be formed by reacting titanium tetrachloride with metallic aluminum. The complex can be represented by the formula TiCl /3 AlCl Examples of the substituted silane compounds represented by the formula (RO),,SiR' and used as alternative component C-1 of the catalyst system are: butoxysilane, phenylmethoxysilane, trimethylethoxysilane, dimethyldiethoxysilane, diphenyldiethoxysilane, tetraethoxysilane, tricyclohexylphenoxysilane, dioctyldi(3-cyclopentyl-1 naphthoxy)silane, eicsosyltri(S-phenylpropoxy)silane, benzyltri(3-methylcyclohexoxy)silane, 3 phenylcyclopentyltridecoxysilane, and the like.

Triethylenediamine, which is used as alternative component C-2 of the catalyst system, is also known as 1,4- diazobicyclo(2.2.2)octane, and has the structure:

Examples of the phosphoramides represented by the formula (R N) P=O and used as alternative component 03 of the catalyst system are:

tris (N,N-dimethyl) phosphoramide,

tris (N,N-dicyclopentyl phosphoramide,

tris (N,N-dibenzyl phosphoramide,

tris N,N-dieicosyl phosphoramide,

tris N,N-di-4,S-dipentyl-Z-naphthyl phosphoramide, tris(N,N-diphenyl phosphoramide,

tris(N,N-diethyl phosphoramide,

tris N,N-diisobutyl phosphoramide, tris(N,N-di-3-octylphenyl phosphoramide,

tris (N,N-di-Z-phenylcyclohexyl phosphoramide,

tris N,N-di- Z-methylcyclopentyl) phenyl phosphoramide,

and the like.

' Examples of the onium halides represented by the formula 'RmZX and used as alternative component C-4 of the catalyst system are the quaternary ammonium halides recited in U.S. 3,147,241, diethyldiphenylammonium fluoride, dioctyldicyclohexylammonium bromide, tetramethylcyclopentylammonium cholride, phenyltribenzylammonium iodide, tetranaphthylammonium chloride, trioctadecyloxonium bromide, methylethylpropyloxonium chloride, benzyldimethyloxonium fluoride, triethyloxonlum chlo- 4 ride, triphenyloxonium iodide, tricyclohexyloxonium bromide, di 3-isobutylphenyl cyclopentyloxonium chloride, ethylmethyloctadecylsulfonium iodide, triphenylsulfonium chloride, trieicosylsulfonium bromide, tri(2-naphthyl)sulfonium iodide, isopropylcyclohexylphenylsulfonium fluoride, ethyltriphenylphosphonium bromide, tridodecylbenzylphosphonium chloride, tetraethylphosphonium fluoride, tetramethylphosphonium iodide, and the like.

Examples of the amides having the formulas and and used as alternative component C-5 of the catalyst system are N,N-dimethylformamide, N,N-dimethylacetamide, N,N-diethylacetamide, N-cyclohexylacetamide, N-t-butylbenzamide, N-methyl-N-phenylacetamide, N-benzylacetamide, n-heptamide, palmitamide, stearanilide, acetanilide, isobutyramide, N,N-di-t-butylurea, tetramethylurea, succinimide, N,N,N'N'-tetramethyladipamide, N-methylisobutyramide, N-benzoylmorpholine, N,N-diacetylpiperazine, n-butyloxamate, ethyloxanilate, ethyl carbamate, and the like.

Examples of the silazanes represented by the formulas R SiNRSiR (R Si) N,

R SiNR'SiR NR''SiR and R'(R SiNH) R, and used as alternative component C-6 of the catalyst system are:

hexamethyldisilazane, N-propyl-hexaphenyldisilazane, N-eicosyl-hexabenzyldisilazane, N-isobutyl-hexamethylcyclohexyldisilazane, hexaeicosyldisilazane, hexa-o-tolyldisilazane,

hexa Z-naphthyl) disilazane, nonacyclopentyltrisilazane, nonamethyltrisilazane, nonaethyltrisilazane, nonamethlcyclohexyltrisilazane, nonabenzyltrisilazane,

nona( 3-phenylcyclohexyl trisilazane,

nona 3 ,5 -diethylphenyl trisilazane, octabenzyltrisildiazane, N,N'-diisobutyl-octamethyltrisildiazane, N,N'-diphenyloctacyclohexyltrisildiazane, octamethyltrisildiazane, octaethyltrisildiazane, N,N-dicyclopentyl-octaeicosyltrisildiazane, polydiphenylsilazane (x=5 polydimethylsilazane (x: 4), polydiethylsilazane (x: 5 O) polydicyclohexylsilazane (x: 10) polydibenzylsilazane (x: 12) polydi-p-tolylsilazane (x= polydi 3 -butylcyclohexyl silazane (x= polydi 6-cyclohexy1decyl silazane (x: 8), polydi (4-cyclohexylphenyl silazane (x: 3 0) polymethylethylsilazane (x==3 5 polycyclohexylmethylsilazane (x= polymethylphenylsilazane (x=.45

and the like.

5: Broad and preferred ranges for the molar ratio of the catalyst components are:

Broad Preferred RAlX2:TiCla-% A101 0. 5:110:1 1:175:1 Component C:TiC1-% Al 0. 25:1-7. 5:1 0. 5:1-5:1 MRnzTiCla-x A101 0. 5:1-7-5:1 1:1-5:1

The polymerization reaction is carried out either in a mass systemi.e., the olefin being polymerized acts as reaction medium-or in an inert hydrocarbon diluent, such as a paraffin, cycloparaflin, or aromatic hydrocarbon having up to 20 carbon atoms per molecule. Examples of EXAMPLE II Propylene was polymerized in a one-liter stirred reactor in 2.5-hour runs at 130 F. and 325 p.s.i.g. with 250 grams of propylene and 1 liter of hydrogen (equivalent to 0.17 mol percent hydrogen in the liquid phase) present in the reaction system:

Mol ratio Total Xylene- RAlX-z: (RO) xS1- catalyst Rate, g./g. Flexural soluble Run R'rxiMRuiTlolaconcn.,wt. Ti complex] modulus, content, wt. %A1Cl (RO)S1R percent hr. p.s.i. l- 0 percent d :2. 0:1 Diphenyldiethoxylsilane- 0. 598 54 191 7. 2 5: 1 .d0 0. 653 88 217 4. 6 5: :1 Tetraethoxysilane. 0. 441 14 5: 1:1 0. 485 34 161 9. 2 0. 536 121 235 3. 6

Based on propylene. ASTM D790-61.

Determined by placing 0.95 g of polymer in a centrifuge tube, adding 95 ml. mixed xylenes, heating for 15 minutes at 285 E, cooling, centrlfugmg, evaporating the solvent from a -ml. aliquot of the supernatant liquid, weighing the resldue, and multlplymg by 400.

hydrocarbons that can be used are pentane, hexane, heptane, isooctane, eicosane, cyclohexane, methylcyclopentane, benzene, toluene, naphthalene, anthracene, and the like, and mixtures thereof. Where an inert diluent is used, the volume ratio of diluent to olefin is in the range of 1:1 to 10:1, preferably 3:1 to 7:1.

The polymerization is conducted at temperatures in the range -60 to 350 F., preferably 100 to 200 F. The pressure is suflicient to maintain the reaction mixture substantially in liquid phase. The reaction time is in the range 10 minutes to 50 hours, more frequently minutes to 10 hours.

Although the invention is illustrated by the polymerization of propylene, any aliphatic olefin having up to 8 carbon atoms per molecule or mixtures thereof can be.

used, such as propylene, l-butene, l-pentene, l-hexene, 3 -methyl-1-butene, 4-methyl-1-pentene, l-octene, and the like. 2'

It is within the scope of the invention to use hydrogen in a concentration of about 0.08 to 0.50 mol percent of the olefin, calculated as the amount present in the liquid phase, for controlling the molecular weight of the polymer.

The following'examples will further illustrate the invention, although it is not intended that the invention be limited thereto.

. I EXAMPLE I Propylene was polymerized in a one-liter stirred reactor in 2.5-hour runs at 130 F. and 325 p.s.i.g. with 250 grams of propylene and 1 liter of hydrogen (equivalent to 0.17 mol percent hydrogen in the liquid phase) present in the reaction system.

EXAMPLE I11 Propylene was polymerized in a one-liter stirred reactor in 2.5-hour runs at 130 F. and 325 p.s.i.g. with 250 grams of propylene and 1 liter of hydrogen (equivalent to 0.17 mol percent hydrogen in the liquid phase) present in the reaction system:

11 Based on propylene.

The above data demonstrate that the addition of a compound of the formula MR results in an increase in productivity of the catalyst system using only three components.

EXAMPLE IV Propylene was polymerized in a one-liter stirred reactor in 2.5-hour runs at 130 F. and 325 p.s.i.g. with 250 grams of propylene and 1 liter of hydrogen (equivalent to 0.17

mol percent hydrogen in the liquid phase) present in the reaction system.

MRir is' triethyl aluminum, Based on propylene.

RAIXa is ethyllaluminum dichloride; Silazane is hexamethyldisilazane;

c Determined by placing 0.95 g. of polymer in a centrifuge tube, adding ml. mixed xylenes, heating for 15 minutes at 285 F., cooling, centrifuging, evaporating the solvent from a 25-ml. aliquot of the supernatant liquid,

weighing the residue, and multiplying by 400.

ASTM D790-61.

Total Mol ratio catalyst Xylenes concn., solublcs, RAlXzzAmide: wt. Rate, wt. Floxural MRnZTlClB' percent g./ln./g. Ti percent modulus, A101 complex p.s.i.Xl0

Run No RAIXQ is ethylaluminum dichloride; Amide is tetramethylurea; MR1, is

triethylaluminum.

b Based on propylene.

weighing the residue, and multiplying by 400.

The above data demonstrate that the addition of a compound of the formula MR results in an increase in productivity, a decrease in the xyleneso1ub1es-i.e., amorphous polymer content of the product-and an increase in the fiexural modulus of the polymer.

EXAMPLE V Propylene was polymerized in a one-liter stirred reactor in 2.5-hour runs at 130 F. and 325 p.s.i.g. with 250 grams of propylene and 1 liter of hydrogen (equivalent to 0.17 mol percent in the liquid phase) present in the reaction system.

ductivity, a decrease in the xylenes-solubles, i.e., amorphous polymer content of the product, and an increase in the fiexural modulus of the polymer, as compared to the properties of the polymer formed in the absence of the MR compound.

We claim:

1. A catalyst system formed on admixing an organometal compound of the formula MR wherein M is a metal of Group I-A, IIA, III-A and IV-A of the Periodic Table, n is the valence of M and R is a radical selected from the group consisting of alkyl, cycloalkyl and aryl having from 1 to 20 carbon atoms with a titanium tri- RAIX is ethylaluminum dichloride:

sium in Runs 3 and 4.

Based on propylene.

(R2N)3P=O is tris(N phosphoramide; MRn is triethylaluminum in Runs 1 and 2 and d N-dimethyl) ethylmagnec Determined by placing 0.95 g. of polymer in a centrifuge tube, adding 95 ml. mixed xylenes, heating evaporating the solvent r weighing the residue, and multiplying by 400.

The above data demonstrate that the addition of a compound of the formula MR results in an increase in productivity, a decrease in xylene-solublesi.e., amorphous polymer content of the productand an increase in flexural modulus of the polymer.

EXAMPLE VI Propylene was polymerized in a one-liter stirred reactor in 2.5-hour runs at 130 F. and 325 p.s.i.g. with 250 grams of propylene and 1 liter of hydrogen (equivalent to 0.17 mol percent hydrogen in the liquid phase) present in the reaction system:

Total Mol ratio catalyst concn., RAIXQ: R ZX: wt. Rate, MRnTiClg-% percent g./hr./g. 101: Ti complex Run N0 for 15 minutes at 285 F., cooling, centrifuging, om a 25-ml. aliquot of the supernatant liquid,

chloride-aluminum trichloride complex of the formula TiCl /sAlCl an organoaluminum dihalide of the formula RAlX wherein X is a halogen and R is a member of the group consisting of alkyl, cycloalkyl and aryl radicals having from 1 to 20 carbon atoms and a silazane selected from the group consisting of R SiNR'-SiR (R Si) N, R Si-NR'fiSiR -NR'-SiR and wherein R is a member of the group consisting of alkyl, cycloalkyl and aryl radicals having from 1 to 20 carbon atoms, R is R or hydrogen and y is an integer from 4 to 50, and wherein the molar ratio of said RAlX compound to said TiCl AlCl compound is in the range of 0.5 :1 to 10:1, the molar ratio of said silazane compound to said TiCl A1Cl compound is in the range of 0.25:1 to 7.5:1 and the molar ratio of said MR compound to said TiCl AlCl compound is in the range of 0.521 to 75:1 and wherein the molar ratio of said RAIX compound to said MR compound is in the range of 5:1 to 5:2.

2. A catalyst system according to claim 1 wherein said silazane is selected from the group consisting of hexamethyldisilazane, N-propyl-hexaphenyldisilazane, N-eicosyl-hexabenzyldisilazane, N-isobutyl-hexamethylcyclohexyldisilazane, hexaeicosyldisilazane, heXa-o-tolyldisilazane, heXa(2-naphthyl)disilazane, nonacyclopentyltrisilazane, nonamethyltrisilazane, 'nonaethyltrisilazane, nonamethylcyclohexyltris ilazane, nonabenzyltrisilazane, no na('3-phenylcyclohexyl)trisilazane, nona(3,5 g diethylphenyntris'ilazane, octabenzyltrisildiazane, octamethyltrisildiazane, octaethyltrisildiazane, N,N'-diphenyloctacyclohexyltrisildiazane, N,N-dicyclopentyl-octaeicosyltrisildiazane polydiphenylsilazane, polydimethylsilazane, polydiethylsilazane, polydicyclohexylsilazane, polydibenzylsilazane, polydi-ptolylsilazane, polydi(3-butylcyclohexyl)silazane, polydi- (6-cyclohexyldecyl)silazane, polydi(4-cyclohexy1phenyl) silazane, polymethylethylsilazane, polycyclohexylmethylsilazane, and polymethylphenylsilazane.

3. A catalyst system according to claim 1 formed by admixing ethylaluminum dichloride, triethylaluminum, hexamethyldisilazane and titanium trichloride-aluminum trichloride complex.

4. A process which comprises polymerizing an aliphatic l-olefin having from 3 to 8 carbon atoms per molecule in the presence of a catalyst which forms on mixing an organometal compound of the formula MR wherein M is a metal of Group I-A, II-A, III-A and IV-A of the Periodic Table, n is the valence of M and R is a radical selected from the group consisting of alkyl, cycloalkyl and aryl having from 1 to 20 carbon atoms with a titanium trichloride-aluminum trichloride complex of the formula TiCl -%AlCl an organoaluminum dihalide of the formula RAlX wherein X is a halogen and R is a member of the group consisting of alkyl, cycloalkyl and aryl radicals having from 1 to 20 carbon atoms and a silazane selected from the group consitsing of R Si-NR'-SiR (R Si) -N, R SiNR'-SiR NR'SiR and,

wherein R is a member of the group consisting of alkyl, cycloalkyl and aryl radicals having from 1 to 20 carbon atoms, R is R or hydrogen and y is an integer from 4 to 50, and wherein the molar ratio of said RAIX compound to said TiCl AlCl compound is in the range of 0.5 :1 to 10:1, the molar ratio of said silazane compound to said TiCl AlCl compound is in the range of 0.25 :1 to 7.5 :1 and the molar ratio of said MR compound to said TiCl /aAlCl compound is in the range of 0.5 :1 to 7.5 :1 and wherein the molar ratio of said RAlX compound to said MR compound is in the range of 5:1 to 5 :2.

5. A process according to claim 4 wherein the catalyst is formed by admixing ethylaluminum dichloride, triethylaluminum, hexamethyldisilazane and titanium t chloride-aluminum trichloride complex.

No references cited.

JOSEPH L. SCHOFER, Primary Examiner S. M. LEVIN, Assistant Examiner U.S. Cl. X.R.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 554 993 Dated January 12 1971 Inventor-( Charles W. Moberly et a1 It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 10 line 18 cancel "No references cited" and insert References Cited UNITED STATES PATENTS 664 4 1961 Stuart 260-93. 7 j ilsv 7/1961 Orzechowski et a1 23-230 3,010 ,787 11/1961 Tornquist 260-94 .9

3 ,088,942 5/1963 Coover 260-93.;

3 ,099 ,647 7/1963 Jeyl et a1 260-93. 7

3 ,189 ,590 6/1965 Coover, Jr et a1 260-93 .7

3 ,2l3,073 10/1965 Langer 260-93. 7

3, 269 ,996 8/1966 Bayer et a1 260-93 FOREIGN PATENTS 827 ,516 2/1960 Great Britain 836, 333 6/1960 Great Britain OTHER REFERENCES Organo Metallic Chemistry, (Feiss) ACS Monograph No 147 Reinhold (1960) pp. 203-204 Signed and sealed this 25th day of May 1971 (SEAL) Attest:

EDWARD M.FLETCHER,JR. WILLIAM E. SCHUYLER, JR.

Attesting Officer Commissioner of Patents 

1. A CATALYST SYSTEM FORMED ON ADMIXING AN ORGANOMETAL COMPOUND OF THE FORMULA MRN WHEREIN M IS A METAL OF GROUP I-A, II-A, III-A AND IV-A OF THE PERIODIC TABLE, N IS THE VALENCE OF M AND R IS A RADICAL SELECTED FROM THE GROUP CONSISTING OF ALKYL, CYCLOALKYL AND ARYL HAVING FROM 1 TO 20 CARBON ATOMS WITH A TITANIUM TRICHLORIDE-ALUMINUM TRICHLORIDE COMPLEX OF THE FORMULA TICL3-1/3ALCL3, AN ORGANOALUMINUM DIHALIDE OF THE FORMULA RALX2 WHEREIN X IS A HALOGEN AND R IS A MEMBER OF THE GROUP CONSISTING OF ALKYL, CYCLOALKYL AND ARYL RADICALS HAVING FROM 1 TO 20 CARBON ATOMS AND A SILAZANE SELECTED FROM THE GROUP CONSISTING OF R3SI-NR''-SIR3, (R3SI3-N, R3SI-NR''-SIR2-NR''-SIR3 AND 